The invention relates to a modular conveyor mat and a conveying module for a modular conveyor mat. Modular conveyor mats are generally known and are used for conveying all sorts of products in a large number of environments. A particularly demanding use for a modular conveyor mat is the conveyance of products through a pasteurizer or a cooler.
An example of this is a tunnel pasteurizer or a tunnel cooler, in which the modular conveyor mat passes through a housing. In the housing, a number of zones are realized in which the temperature of the products to be conveyed can be influenced with heat exchanging medium. An example is a beer can or beer bottle to be pasteurized which is passed, with the aid of the modular conveyor mat, through a number of temperature zones within the housing, in which hot water is sprayed on the bottle with each time, per zone, a different temperature, for instance 40-60-40-20° C. In such a tunnel pasteurizer or tunnel cooler, the modular conveyor mat can, for instance, be 6.5 meters wide and up to 40 meters long. Such a conveyor conveys the products at a velocity of for instance approximately 0.5-1 m/min and can have a capacity of, for instance, approximately 70,000 beer bottles an hour. In the water zones, per m2 of track surface, approximately 25 m3 of water is sprayed per hour on the beer bottles. Fox a more efficient use of water, within the housing, two conveyors can be arranged one above the other.
On account of their favourable cost price and light weight, as a rule, it is preferred to use plastic modules in modular conveyor mats. However, for some uses, for instance with heavily loaded tunnel pasteurizers, it has been proposed to provide a hybrid conveyor mat. In such a hybrid conveyor mat, an endless base structure composed of metal modules is used, which is provided with plastic product carriers forming the conveying surface.
Here, the base structure of the conveyor mat is of modular design from metal elements, which absorb the tensile forces that are formed upon conveyance, and which are, furthermore, form-retaining and wear resistant and resistant to aging. The plastic product carriers facilitate handling the products, for instance during transfer from or to a different conveyor. As they do not form part of the base structure, the form stability and wear resistance of the product carrier is less critical, so that designing them in plastic is well possible. Examples of such hybrid conveyor mats are described in, for instance, U.S. Pat. No. 5,197,591 and U.S. Pat. No. 6,615,979 in the name of Ashworth.
A drawback of the known hybrid conveyor mats is that often, they are still not sufficiently strong.